Drawing press



June 26, 1923. 1,459,905

A. A. BYERLEIN DRAWING PRES S Fileqf b lpmgzllem 2 Sheets-Sheet 2 Patented June 26, 1923.

1,452,953 PATENT OFFlE.

ARTHUR A. BYERLEIN, OF TOLEDO, OHIO, ASSIGNOR TO THE TOLEDO MACHINE & TOOL COMPANY, OF TOLEDO, OHIO, A CORPORATION OF OHIO.

' DRAWING PRESS.

Application filed. November 3, 1920. Serial No. 421,491.

T 0 all whom it may concern:

Be it known that I, ARTHUR A. BYERLEIN, a citizen of the United States, and a resident of Toledo, in the county of Lucas and State of Ohio, have made an Invention Appertaining to Drawing Presses; and I do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same, reference being had to the accompanying drawings, and to the characters of refer ence marked thereon, which form a part of this specification.

This invention relates to drawing presses, and particularly to those of the type in which the blank holder precedes the work shaping member in its engagement of the blank and then dwells or pauses and firmly holds the blank during the shaping operation. The invention also relates to the type of machine shown and described in United States Letters Patent No. 1,176,897 of March 28, 1916. Y

The object of my invention is to provide a simple and efficient operating means for the blank holding and shaping members whereby to enhance the practicability and commercial value of machines of this class.

The invention is fully described in the following specification, and while, in its broader aspect, it is capable of embodiment in numerous forms, a preferred embodiment thereof is illustrated in the accompanying drawings, in which- Figure 1 is a front elevation of a ma chine embodying the invention, with parts broken away, and with the die members removed and the blank holding and shaping members in elevated position. Fig. 2 is a central vertical section thereof with the lower portion in full and with the die memhers in position. Fig. 3 is an enlarged section on the line 3-3 in Fig. 2, Fig. 1 is a fragmentary cross-sectional view of the machine, with the blank holder and shaping memb rs at the limit of their downward strokes, and Fig. 5 is an enlarged sectional detail of a part of the machine.

Referring to the drawings, 1 designates the base of the machine, forming on its top the bed plate 2, having a die 3, in the present instance of male form, mounted thereon. A stripper member 41 is mounted in a recess in the die, and after each work shag ing operation is elevated by suitable mechanism to strip a shaped work piece from the die. The stripper operating mechanism forms no part of the present invention and need not therefore be described.

The machine frame has the customary side uprights 5 and connecting top crosspiece 6, the uprights 5 forming guides for directing the vertical reciprocatory travel of the blank shaping member 7, carrying the shaping die 8 on its bottom for cooperating with the die 3 in the shaping operation. The member 7 is of hollow form and has the blank holder plunger 9 mounted for reciprocatory movements therein. This plunger has pins '10 projecting downward through the bottom of the shaping member 7 for free reciprocatory movements relative thereto and carrying a blank holding pad 11 at their lower endswithin a recess in the upper die 8 for coacting with the central elevated portion of the male die 3 to hold a blank during a shaping operation.

I The customary crank shaft 12 is mounted in the upper portion of the frame and has cranks 13, 13 at'opposite ends thereof which are connected by connecting rods or pitmans 14 with the respective ends of the shaping member 7, whereby the shaping member has reciprocatory movements imparted thereto from a turning of the cranks.

The blank-holder 9 is provided at its top above each end thereof and without the top of the shaping member 7 with a cross-bar 15, which is connected with the plunger by rods 16 and is provided at its ends with vertical guide rods 17, which project at their ends loosely through guide bosses 18 and 19 provided respectively on the sides of the member 7 and of the frame top 6. Each cross-bar 15 carries a roller 20, which is acted. on during a predetermined portion of a revolution of the crank shaft by a registering cam 21 on such shaft to effect first a lowering of the blank holder 9 at a predetermined speed with respect to the lowering of the shaping member 7 then to cause the blank holder to dwell during the blank shaping operation, and then to permit the blank holder to raise to its normal position. The raising or return of the blank holder to its normal position is effected by. the engagement of adjustable studs 22 on the top of the member 7 with registering spring bump- 23 on the cross-bars 15 when the member 7 has raised a predetermined extent from its lowered position.

The desired relative adjustment of the shaping member 7 and blank holder 9 is obtained by a shortening or lengthening of the members 16 between the plunger 9 and crossbars 15, which is effected by a turning of the members 16 to thread them into or out of one or the other of the members which they connect. A uniform adjustment of the connecting members 16 is obtained by providing each member with a worm-wheel 24; in mesh with driving worms on a common worm shaft 25, as is well understood in the art. 7

It, is evident, in the operation of a ma chine equipped with my improvement, that the blank-holder plunger 9 and shaping member 7 lower together upon a turning of the crank shaft 12 until the blank holder pad rests on the work and that the cams 21 thenact to cause the blank holder to dwell during the remainder of the downward blank shaping movement of the member '7 and for a portion'of its upward stroke due to the prolonged engagement of the neutral portion a of the cams with therollers 20. When the shaping operation is completed by reason of the member 7 completing its downward stroke said member is positively raised to its elevated position and when it has raised a predetermined extent the thrustshaping operation, the center of theblank, in being driven into the, cavity of the female die, is more or less buckled and warped and in some cases to such an extent as to prevent the formation of perfect work.

I wish it understood that my invention is not limited to any specific construction, arrangement, or form of the parts, as it may be changed and modified in numerous r-espects without departing from the spirit of the claim. I

-Having thus described my invention, what "I claim as new, and desire to secure by Letters Patent, is,-

In a drawing press, a frame, a hollow vertically reciprocable shaping plunger carried by the frame, a vertically reciprocable blank holding plunger in the shaping plunger, vertically alinejd guides carried by the frame and the-opposite sides ofthe shaping plunger, crossbars spaced above the upper end of the blank holding plunger, means in" said space for adj ustably connecting the cross bars to the upper end of the blank. holding plunger, guide rods projecting upwardly and downwardly from and secured intermediate their ends to the cross-bars and received in said guides, adjustable studs in the space, between-the cross bars and the blank holding plunger, extending upwardly from the upperend of the shaping plunger, spring bumpers carriedby the cross bars and in registry with said studs and' also arranged in the space between the cross bars and the blank holding plunger, a crank shaft carried by the frame and connected to the shaping plunger to actuate the latter, and cams on the crank shaft located in close relation to the tops of the cross bars and in the space between the upper ends of the guide rods to actuate the latter and thereby the blank holding plunger.

In testimony whereof I have hereunto signed my name to this specification.

ARTHUR A. BYERLEIN. 

